Foldable construction block

ABSTRACT

A construction block foldable from a flat sheet of material to form a container which may be filled with available solid material and stacked with other such blocks in staggered courses. Interlock tabs project from the center of one horizontal wall of the block and the other horizontal wall is provided with a lateral, central slot arranged to receive interlock tabs from other such blocks. The block may be folded to provide either, two symmetrical lateral interlock tabs for making lateral wall runs, or to provide lateral and transverse tabs for wall corners.

United States Patent Huber et al. 1 51 Nov. 14, 1972 [54] FOLDABLE CONSTRUCTION BLOCK 3,412,502 11/1968 Riches ..46/25 [72] Inventors: William C. Huber, Seabrook; Dale O G EN O APPLICATIONS L. Ritter, Houston, both of Tex. 541,920 4/1956 Italy..., ..229/Dl G. ll Ass1gnee= The United States of America as 540,196 10/1941 Great Britain ..52/594 represented by the Administrator of the National Aeronautics and Space Primary Examiner-Alfred Ct Perham Administration, by said Huber Attorrpy-EdwardK. Fein, Marvin F. Matthews and 22 Filed: Jan. 18, 1971 v [21] Appl. No.: 107,298 [57] ABSTRACT A construction block foldable from a flat sheet of [52] US. Cl.'. ..52/284, 52/594, 229/DIG. 11 mat r al o rm a eontainer ay be fil ith 51 Int. Cl 1/10 available solid material and stacked with other h 58 Field of Search ....229/38, DIG. 11; 52/594, 593, blocks in Staggered eemees- Interlock tabs P j 52/234, 578 from the center of one horizontal wall of the block 1 and the other horizontal wall is provided with a lateral central slot arranged to receive interlock tabs R f C ted v [56] e erences l from other such blocks. The block may be folded to UNITED STATES PATENTS provide either, two symmetrical lateral interlock tabs for making lateral wall runs, or to provide lateral and 1,881,900 10/ 1932 Oman et a1. ..229/38 X transverse tabs for wallcomers 422,901 3/1890 Amett ..52/594 X 3,368,316 2/1968 Crowder ..52/593 4 Claims, 2 Drawing Figures PATENTEDNHVWHYZ 3.702.520

2 E 312-"... j'ff- 170/? Z fF/ffer INVENTORS ATTORNEY 1 FOLDABLE CONSTRUCTION BLOCK ORIGIN OF THE INVENTION A co-inventor of the invention described herein is an employee of the United States Government. Accordingly, this invention may be manufactured and used by or for the Government of the United States of America for Governmental purposes without the payment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to on site formable building blocks.

2. Description of thePrior Art Frequently in the proposed construction of low-cost permanent or semi-permanent static structures suitable for human habitation, the cost of construction using conventional techniques would exceed-the value of the proposed structure. This problem is particularly encountered when housingis proposed for remote areas in underdeveloped countries. In many such instances, there are no locally available inexpensive building materials and the cost of transporting conventional supplies from an available source is prohibitive. This problem also arises in other situations whena structure is needed for short-term useand would have little or no salvage value.

One prior art solution to this problem has been the use of locally available water, clay'and'binder material, such as straw, for on site preparation of adobe bricks which are, in turn, used for construction ofthe structure. This solution is only applicable in selected geographicalareas where the necessary materials and the climate permit. Even 'in those instances, a certain minimum of construction tools is required and the preparation process can be lengthy.

-An alternate solution frequently adopted in these situations is the use of sand bags or similar containers which may be filled with any available material and stacked to form walls of the structure. This solution is frequently unsuitable, however, due to the instability of the walls and the inability of the walls to support a roof load.

Neither of the foregoing prior art solutions is suitable when a relatively dust and lint free environment is required within the structure. This problem is frequently encountered when a temporary medical treatment facility must be constructed in a remote area, for example.

Another solution to this problem is shown in US. Pat. No. 3,665,669, issued May 30, 1972, to one of the co-inventors of the instant invention, William C. Huber, entitled Foldable Construction Block and Method of Construction. The construction blocks disclosed in that patent overcome many prior I art problems by providing foldable construction blocks which may be assembled, filled and stacked in courses SUMMARY OF THE INVENTION The invention disclosed herein involves a construction block which may be assembled by folding a pre-cut flat sheet of material to form a closed container having: single or double thickness, laterally symmetrical, interlock tabs projecting from one horizontal wall; and, a lateral interlock tab receiving slot generally in the center of the other horizontal wall. The block may be folded to provide either two laterally symmetrical interlock tabs for lateral wall runs or one lateral and one transverse tab for wall corners. Due to the lateral symmetry of the block, a plurality of these blocks may be stacked one upon another without creating transverse steps in the wall surface. It is preferred that the ratio of the length of the side walls to end walls of the block be approximately 2 to l to provide corner symmetry.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is n isometric view showing a partially constructed wall and corner using the block of this invention.

FIG. 2 is a layout of the blocks shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, a preferred embodiment of this invention is shown in plan layout in FIG. 2 and in folded isometric in FIG. 1. This form of the invention may be die cut from a blank, such as a flat sheet of material, in a single die cutting operation, following the layout of FIG. 2, and may be folded at the construction site along the indicated broken lines to form the lateral wall block generally designated as 10 in FIG. 1 or to form the corner wall block generally designated as 11 in FIG. 1. Throughout the balance of this description,

. the horizontal wall of the blocks having interlock tabs projecting therefrom will be referred to as the bottom of the blocks and the horizontal wall having the central lateral interlock tab receiving slot will be referred to as the top of the blocks. These references are for convenience of discussion only, as these blocks may be stacked with either upwardly or downwardly projecting interlock tabs to form a wall, as described below.

The flat blank of FIG. 2 has four substantially rectangular adjoining panels which form the end walls 12 and 14 and side walls 13 and 15 of the completed block. Depending from end 12 are bottom closure flaps 16 and 17 having closure tabs 18 and 19, respectively, thereon, which flaps and tabs are arranged to be folded along fold lines 20 and 21, respectively, as described below. Extending downward from side 13 are bottom flaps 22 and 23 having closure tabs 24 and 25, respectively. These flaps and tabs are arranged to be hinged along fold lines 26, 27 and 28, as described below. Depending from end wall 14 are bottom flaps 29 and 30, which flaps are hinged along fold line 31 during assembly of the block. The remainder of the bottom of the block depends from side 15 and is formed by flaps 32 and 33 and corresponding closure tabs 34 and 35, respectively. These panels are arranged to be hinged along fold lines 36, 37 and 38 during block assembly.

The top horizontal surface of the block, the interlock tabs and the central block dividers are formed during assembly of the block from the panels which extend upwardly from ends 12 and 14 and sides 13 and 15. Panels 39-42 extending upwardly from end 12 form the transverse interlock tabs for the completed corner wall block configuration when folded along lines 43-46, as described below. Panel 47, which is hinged to side 13 along line 50, forms one-half of the top cover of the assembled block, with panel 54, hinged to side 15 along line 57, forming the other one-half of the top. Panels 48 and 49 and panels 55 and 56 form lateral central dividers for the assembled block and are hinged to panels 47 and 54, respectively, along fold lines 51 and 52 and fold lines 58 and 59, as indicated. The lateral interlock tabs which extend downwardly from the center line of the completed lateral wall block configuration are formed from tabs 49a and 49b on panel 49 and from tabs 56a and 56b on panel 56.

Since tabs 49a and 56b are utilized only in the blocks 10 used for lateral wall runs, these tabs are provided with fold lines 53 and 60, respectively, along their bases so that they may be folded 180 under when a comer block 11 is being assembled, as described below. The final top closure portion of the block is formed by flaps 61 and 62 which extend upwardly from end 14 and are hinged to end 14 along fold lines 63 and 64, respectively.

The first step in forming a construction block from the blank shown in FIG. 2 is to fold the blank intermediate its opposite ends along central fold line 65. While this fold may be made in either direction, the remainder of this discussion will treat the surface of the block shown in FIG. 2 as the outside surface of the block. For storage and shipment of the block blanks, it would be convenient to make a 180 fold along line 65, with that fold opened to 90 at the time of assembly of the block. After making the 180 fold along line 65, tab 68 which extends outward from end 12 is folded over 180 along line 69 and is secured to the outside end of side 15, as described below. At the construction site, the 180 folds along lines 65 and 69 are opened to 90 and similar 90 outward folds are made along lines 66 and 67, thereby forming the blank into a rectangular, open-top and open-bottom configuration. Next, flaps 61 and 62 are folded inward 90 toward the center of the block along lines 63 and 64, respectively.

At this point, the partially completed block can be folded into either a lateral wall block 10 or a corner wall block 1 1. To form a block 10, panels 39 and 40 are folded inward 90 along lines 43 and 44 into overlapping relation with flaps 61 and 62, so that panels 39-42 and flaps 61 and 62 extend horizontally across the top of the block. No fold is made along lines 45 and 46 for this block. Temporary downward folds of approximately 45 are now made along lines 52 and 59 and 90 folds are made along lines 50 and 51 and lines 57 and 58. As these 90 folds are made, panels 49 and 56 are directed into the block through the openings between panels 41 and 42 and flaps 61 and 62. As the 90 folds along lines 50 and 51 and lines 57 and 58 are completed, tabs 49a and 49b and tabs 56a and 56b will protrude out of the lateral center line of the bottom of the block and the temporary folds along lines 52 and 59 are opened. Tabs 490 and 56b are adjacent and parallel, as are tabs 49b and 56a, thereby forming double thickness central, lateral interlock tabs. Panels 48 and 49 and panels 55 and 56 are now flat sheets and form central vertical walls which laterally bisect the block.

With the top and sides of a lateral wall block 10 now completed, the partially completed block may be turned upside-down and each half of the block may be filled with available solid material. The block 10 is completed by folding flaps 16, 17, 29 and 30 inward along lines 20 and 31, respectively, and by folding bottom flaps 22, 23, 32 and 33 inward 90. Closure tabs 24, 25, 34 and 35 are then folded down 90 and are forced into the block adjacent the central vertical walls 49 and 56.

If the block blank is to be formed into a corner wall block 11, rather than a lateral wall block 10, the initial 90 folds along lines 65, 66, 67, 69, 63 and 64 are made as as described above. Then 90 downward folds are made along lines 43-46 so that panels 41 and 42 extend through the inside of the block parallel to the ends 12 and 14 and extend out the bottom of the block to form transverse interlock tabs. Folds of are then made along lines 53 and 60 so that tabs 49a and 56b are doubled back on panels 49 and 56, respectively, since tabs 49a and 56b are not used in comer block 11. Temporary downward folds of approximately 45 are then made along lines 52 and 59 and 90 downward folds are made along lines 50 and 51 and along lines 57 and 58. As these 90 folds are made, panels 49 and 56 are directed into the block through the openings between panels 39,41 40,42 and flaps 61-62. As the 90 folds along 50,51 and 57,58 are completed, tabs 49b and 56a will protrude out of the center of the bottom of the block and the temporary folds along lines 52 and 59 are opened. Panels 48 and 49 and panels 55 and 56 are now flat sheets and form central vertical walls which laterally bisect the block.

With the top and sides of a corner wall block 1 1 now completed, the partially completed block may be turned upside down and each half of the block may be filled with available solid material. To close the bottom of the block, flaps 16, 17, 29 and 30 are folded inward 90 along lines 20 and 31, respectively, and tabs 18 and 19 are folded outward 90 along lines 21 so that tabs 18 and 19 are parallel and adjacent to panels 41 and 42. Closure of the bottom is completed by folding tabs 24, 25, 34 and 35 90 downward and by folding flaps 22, 23, 32 and 33 over 90 so that tabs 24, 25, 34 and 35 extend into the block adjacent the central vertical walls.

This construction block may be formed of any desired sheet material, such as sheet steel or plastic. However, waterproofed cardboard is preferred due to its weight, flexibility and cost. When forming the blank of cardboard, the fold lines may be scored or pressed into the blank during or after the die cutting to form hinges between the various panels. Using cardboard, the connection between tab 68 on end wall 12 and side wall 15 may be provided in any conventional manner, as by the use of staples through tab 68 and side 15 or by the use of glue or adhesive tape.

Although not required, it is desirable to form the blocks with length b to width a ratio (as shown in FIG. 1) of 2 to 1 so that comers formed with the blocks may conveniently assume an interlocking planar relationship. It has been found that a practical size for the blocks is 16 inches long by 8 inches wide by 8 inches high. Using this size, the blocks, when filled with available solid material, are not too heavy to be moved by one person and yet have sufficient base area and strucwith the interlock tabs 49b and 56a extending either upward or downward, since both horizontal surfaces of the block are closed. If this first row is laid with upwardly extending tabs, then corner blocks 11 should be used for all corners on this row. When this first row is laid with tabs 49b and 56a downward and folded over,

I either type of block may be used in any location. In

either case, blocks 11 are used for corners on subsequent rows and blocks are used for lateral wall runs. If desired, a more rigid and permanent wall can be constructed by using adhesive or glue to bind the blocks together. If the blocks are not bound together, they may be conveniently unstacked, emptied and unfolded, and subsequently re-used to construct other structures.

Further modifications in the apparatus of this invention will become apparent to those skilled in the art in view of the foregoing description.

What is claimed is:

l. A construction block foldable from a flat sheet of material to form a container suitable for filling with available solid material and which may be stacked with other such blocks in staggered interlocking relation, said block comprising:

a box member having a pair of side walls, a pair of end walls connected to said side walls at adjacent vertical edges and top and bottom horizontal walls connected to said side walls and arranged for closing the top and bottom of said box member;

a longitudinal vertical partition formed by upward extensions of said bottom horizontal wall forming a longitudinal slot means in said bottom horizontal wall; and

interlock tab means extending from said longitudinal vertical partition through the construction block and projecting beyond said top horizontal wall arranged to be insertable into the longitudinal slot means of another of said blocks in a lateral wall run.

2. The invention as claimed in claim 1 wherein:

the ratio of the length of said side walls to said end walls is approximately 2 to l.

3. The invention as claimed in claim 1 comprising:

transverse interlock tab means projecting from said top horizontal wall, said transverse tab means being disposed in a plane generally parallel to said end walls and more proximate of one end wall, arranged to be insertable into the longitudinal slot means of another of said blocks at an angle of thereto.

4. The invention as claimed in claim 3 wherein:

the ratio of the length of said side walls to said end walls is approximately 2 to 1 and the ratio of the distances from said one end wall to said transverse slot means and to said other end wall is approximately 1 to 4. 

1. A construction block foldable from a flat sheet of material to form a container suitable for filling with available solid material and which may be stacked with other such blocks in staggered interlocking relation, said block comprising: a box member having a pair of side walls, a pair of end walls connected to said side walls at adjacent vertical edges and top and bottom horizontal walls connected to said side walls and arranged for closing the top and bottom of said box member; a longitudinal vertical partition formed by upward extensions of said bottom horizontal wall forming a longitudinal slot means in said bottom horizontal wall; and interlock tab means extending from said longitudinal vertical partition through the construction block and projecting beyond said top horizontal wall arranged to be insertable into the longitudinal slot means of another of said blocks in a lateral wall run.
 2. The invention as claimed in claim 1 wherein: the ratio of the length of said side walls to said end walls is approximately 2 to
 1. 3. The invention as claimed in claim 1 comprising: transverse interlock tab means projecting from said top horizontal wall, said transverse tab means being disposed in a plane generally parallel to said end walls and more proximate of one end wall, arranged to be insertable into the longitudinal slot means of another of said blocks at an angle of 90* thereto.
 4. The invention as claimed in claim 3 wherein: the ratio of the length of said side walls to said end walls is approximately 2 to 1 and the ratio of the distances from said one end wall to said transverse slot means and to said other end wall is approximately 1 to
 4. 